Let's break this down. We're going to add 8953 and 7136 together.

Step 1: We'll start by adding the digits 3 & 6 in column 1 and get 9.

Step 2: We'll start by adding the digits 5 & 3 in column 2 and get 8.

Step 3: We'll start by adding the digits 9 & 1 in column 3 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 8 & 7 in column 4 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

So, 8953 + 7136 = 16089.

